<!DOCTYPE HTML>
<html>
<body style="background:rgb(0,0,0);">
  <div style="position:fixed;left:0;top:0;width:200px;height:300px;background:rgba(255,255,255,0.5);">
    <div style="margin-top:200px;height:100px;background:rgb(0,0,0);"></div>
  </div>
</body>
</html>
